“Binocular vision” is sight in which both eyes are used together. Binocular viewing of a scene creates two slightly different images of the scene in the two eyes due to the eyes' different positions on the head. “Stereopsis” is the perception of depth that is achieved when someone with normal binocular vision views a scene with both eyes. However, stereopsis is not usually present when viewing a picture of a scene with both eyes.
“Stereoscopy is a technique for creating or enhancing the illusion of depth in an image (i.e. a picture) by means of stereopsis for binocular vision. The stereoscopy method utilizes two offset images separately to the left and right eye of the viewer where they are combined by the brain into a single multi-dimensional image. To make three-dimensional images or motion pictures, stereoscopic camera apparatuses are utilized that include a beam splitter and several cameras. The beam splitter is a device that splits a beam of incoming light, in two. Each split beam of light is captured as an image by a camera.
Three-dimensional beam splitters can be used on land and underwater. However, when used underwater, the stereoscopic camera apparatuses must be in a sealed housing. The sealed housing has a large flat window or port and contains the beam splitter, lenses and cameras. The addition of a flat window on the sealed housing creates optical aberrations, distortions and significantly degraded the optical quality of the captured images. Moreover, the sealed housing is a larger, more cumbersome, apparatus.
For the foregoing reasons, it would be desirable to have a stereoscopic camera apparatus with a beam splitter that can be used underwater without a sealed housing. The solution is found in the present disclosure for a submersible stereoscopic beam splitter, which comprises a fully submersible beam splitter and optics system with no sealed housing.